Broiler exhaust unit having hood structure with pivoting heat shield

ABSTRACT

A broiler exhaust unit includes a hood structure with a heat shield pivotally connected thereto. The heat shield is movable between a shielding position and a non-shielding position and one or more supporting hinges provide the pivotal connection and also provide support for the heat shield sufficient to prevent gravity from causing the heat shield to pivot out of at least the non-shielding position.

TECHNICAL FIELD

[0001] The present invention relates generally to exhaust hoods utilizedin kitchens of commercial establishments such as restaurants andcafeterias and, more particularly, to broiler exhaust hood including apivoting heat shield that is stably supported when moved out of its heatshielding position.

BACKGROUND

[0002] Kitchen ventilator exhaust hoods have long been provided for thepurpose of exhausting steam, smoke and particulates such as grease thatare produced by cooking appliances, such as broilers, in the commercialcooking environment. In the case of exhaust hoods used in connectionwith conveyor type broilers, it is known to provide a heat shield on thefront panel of such hoods, the purpose of the heat shield being to blockradiant heat produced by the broiler. To provide access to the broiler,in the past such heat shields have been removable. Other prior art heatshields have been hingedly connected to the front panel of the hood,with a kickstand type structure also provided to support the heat shieldwhen it is pivoted into a non-shielding position. Still other prior artmovable heat shields have been connected to the hood structure alongslots having notches that allow the hood structure to be moved away fromits shielding position and supported in one or more non-shieldingpositions. Each of these prior art heat shield attachments schemessuffers from certain disadvantages such as difficulty in manufacture andcleanability, increased manufacturing costs, and or inconvenience ofoperation by the end user.

[0003] Accordingly, it would be desirable to provide a broiler exhausthood with simple, effective heat shield attached thereto.

SUMMARY

[0004] In one aspect, a broiler exhaust unit includes a hood structureincluding a front panel, a real panel and first and second side panels,the hood structure including an open bottom for positioning over abroiler. A heat shield is pivotally connected to a lower end of thefront panel for movement between a shielding position toward the openbottom and a non-shielding position away from the open bottom. At leastone friction hinge pivotally connects the heat shield to the hoodstructure such that when the heat shield is in the non-shieldingposition or any one of a plurality of positions between thenon-shielding position and the shielding position, the at least onefriction hinge provides support for the heat shield sufficient toprevent gravity from causing the heat shield to pivot out of suchpositions.

[0005] In a further aspect, a broiler exhaust unit includes a hoodstructure including an air intake for positioning over a broiler and atleast one grease extraction baffle therein. A heat shield is pivotallyconnected to a lower part of the hood structure for movement between ashielding position toward the air intake and a non-shielding positionaway from the air intake. At least one supporting hinge pivotallyconnects the heat shield to the lower part such that when the heatshield is in the non-shielding position the at least one supportinghinge provides support for the heat shield sufficient to prevent gravityfrom causing the heat shield to pivot out of the non-shielding position.

[0006] In another aspect, a kitchen exhaust unit for use in connectionwith a cooking appliance such as a broiler includes a hood structureincluding an air intake for positioning over a cooking appliance and atleast one grease extraction baffle within an interior of the hoodstructure. A heat shield is pivotally connected to a lower part of thehood structure for movement between a shielding position toward the airintake and a non-shielding position away from the air intake. At leastone supporting hinge pivotally connects the heat shield to the lowerpart, and the at least one supporting hinge provides support for theheat shield sufficient to prevent gravity from causing the heat shieldto pivot out of the non-shielding position.

BRIEF DESCRIPTION OF DRAWINGS

[0007]FIG. 1 is a perspective view of one embodiment of a broilerexhaust unit including a hood structure with pivoting heat shield;

[0008]FIG. 2 is a side elevation of the broiler exhaust unit positionedover a broiler and with the interior of the hood structure shown;

[0009]FIG. 3A is an enlarged partial cross-section illustrating theshielding position of the heat shield; and

[0010]FIG. 3B is an enlarged partial cross-section illustrating thenon-shielding position of the heat shield.

DESCRIPTION

[0011] Referring to FIG. 1, a perspective view of a broiler exhaust unit10 defined by an exterior hood structure 12 is shown. The illustratedhood structure includes a front panel 14, rear panel 16 and side panels18 and 20, with the side panels 18 and 20 extending lower than the frontpanel 14. The panels 14, 16, 18 and 20 define an open bottom area 22 ofthe hood structure 12 that is positioned over a broiler 24 (FIG. 2) orother cooking appliance and acts as an air intake during operation ofthe exhaust unit. The lower portions 26 and 28 of side panels 18 and 20are also slanted rearward in the illustrated embodiment.

[0012] Referring to FIG. 2, an interior of the exhaust hood 12 is shownand includes one or more grease extraction baffles 30 along a flow paththrough the hood. The grease extraction baffles 30 force air to turnwhen traveling through the hood to be exhausted, causing greaseparticles and other particulates to fall out of the air flow. Theseparticles are collected within the hood and can be cleaned out usingautomated cleaning systems or manually through the use of a removablegrease drawer 32 (FIG. 1). Cleaning and or fire suppression within theinterior of the hood structure 12 may be provided by one or more pipingarrangements 34. An upper part of the hood structure 12 is typicallyconnected to an exhaust path 36 at the installation site, with theexhaust path 36 typically including one more blowers for drawing airthrough the hood structure 12 as indicated by the arrows. Alternatively,the hood structure 12 may include its own internally located blower. Theexhaust path 36 may also include exhaust filtering technologies, such asa catalytic converter, to facilitate meeting any applicableenvironmental air standards.

[0013] In the case of the broiler 24 of FIG. 2, the broiler may be aconveyor type broiler commonly used for cooking meat products such ashamburgers in fast food establishments. The illustrated broiler 24 maybe moved from beneath the hood structure 12, which is typically fixed inplace when installed, to facilitate cleaning within the hood structure12 or maintenance within the hood structure 12.

[0014] A heat shield 40 is pivotally connected to the lower end of frontpanel 14 to deflect radiant heat put off by the broiler 24. The heatshield 40 may include a number of slots or other openings 42therethrough, with radiant heat deflectors 42 extending downwardtherefrom when the heat shield is in its shielding position shown inFIGS. 1, 2 and 3A. During operation of the blower associated with thehood structure 12, air is also drawn in through the slots 42.

[0015] As previously noted, the heat shield 40 is pivotally connected tothe hood structure 12, facilitating movement of the heat shield betweenthe shielding position of FIG. 3A and the non-shielding position of FIG.3B. In the illustrated embodiment the shielding position of the heatshield 40 is downward and toward the open bottom 22 of the hoodstructure 12 and the non-shielding position is upward and away from theopen bottom 22. In the illustrated embodiment the heat shieldingposition is a position in which the heat shield is adjacent the lowerportions 26 and 28 of side panels 18 and 20, and the non-shieldingposition is a position in which the heat shield is angled slightlyupward from horizontal. It is recognized that the non-shielding positionmay be some other position in which the heat shield is at some otherangle, such as pivoted upward against the exterior face of the frontpanel 14, and in any case there may be multiple positions of the heatshield that would be considered non-shielding. When the heat shield 40is in the shielding position (FIG. 3A) the upper part 50 of the broiler24 typically extends above the lower part of the heat shield 40. Theheat shield is therefore moved to the non-shielding position (FIG. 3B)when it is desired to roll the broiler 24 from beneath the hoodstructure 12 or when it is desirable to have access to the upper part 50of the broiler 24 or to certain interior parts of the hood structure 12.It is therefore important to provide the ability for the heat shield 40to be maintained in the non-shielding position without requiring aperson to hold the heat shield 40 in such position. Such functionalityis provided in by the use of one or more supporting hinges 60 to connectthe heat shield 40 to the hood structure 12. In the illustratedembodiment four spaced apart supporting hinges 60 are provided, but moreor less could be used.

[0016] As used herein the term “supporting hinge” is intended toencompass hinges that provide support for the heat shield 40 to hold theheat shield against gravity caused pivoting at least when the heatshield 40 is in the heat shielding position.

[0017] In one embodiment the supporting hinge or hinges may comprise afriction hinge or hinges. A “friction hinge” is broadly defined as adevice with torque between to two parts, such as two hinge plates or ahinge plate and a pivot rod or pin, on a common axis. Exemplary types offriction hinges include the “Reel” clip type, the friction disk type,the “question mark” band type, the roll pin type and the tapered shafttype. A detent hinge is a device with repeatable soft stops in one ormore positions between two parts on a common axis. While not a truefriction hinge, detent hinges are in fact commonly referred to asfriction hinges and the term “friction hinge” as used herein shall alsoencompass detent hinges. Many of these various friction hinges areavailable from REELL Precision Manufacturing Corporation of St. Paul,Minn. (www.reell.com), or from Southco (www.southco.com). Exemplaryfriction hinge constructions are also described in U.S. Pat. Nos.6,301,478, 5,918,348 and 5,079,799, the specification of each of whichis hereby incorporated by reference.

[0018] Where friction hinges are used to pivotally connect the heatshield 40 to the hood structure 12, when the heat shield is in thenon-shielding position or any one of a plurality of positions betweenthe non-shielding position and the shielding position, the frictionhinge or hinges provide support for the heat shield 40 sufficient toprevent gravity from causing the heat shield 40 to pivot out of suchpositions. In other words, the hinge or hinges themselves are all thatis required to prevent gravity from causing the heat shield 40 torotate, but are configured to enable an operator to move the heat shieldby applying a movement force sufficient to overcome the supporting forceor torque of the friction hinge or hinges. Where the friction hinge orhinges are constant torque hinges or some other true friction hinge, thehinge or hinges may prevent gravity from causing the heat shield 40 topivot out of any one of a continuous range of positions between thenon-shielding position and the shielding position. Where the frictionhinge or hinges are detent hinges, the hinge or hinges may preventgravity from causing the heat shield 40 to pivot out of any one of aplurality of discrete positions between the non-shielding position andthe shielding position.

[0019] The friction hinge or hinges may also provide sufficient supportto prevent gravity from causing the heat shield 40 to pivot out of theshielding position. Nonetheless, a latch mechanism 62 may be provided onthe heat shield 40 for holding the heat shield 40 in the shieldingposition. The illustrated latch mechanism 62 includes a rotatable handle64 with a portion extending through the heat shield 40 to an internallylocated and rotatable bracket 66. The bracket 66 is used to engage aninternal structure and hold the heat shield from rotation until thehandle 64 is rotated to move the bracket 66 out of engagement with theinternal structure.

[0020] In another embodiment, the supporting hinge or hinges may beformed by spring-loaded hinges that bias the heat shield 40 toward itsnon-shielding position. In such cases, the latch mechanism 62 may beconfigured to automatically latch when the heat shield 40 is moved toits shielding position. When the latch mechanism is subsequentlyreleased by handle 64 or other actuator, the spring-loaded hinges causethe heat shield to automatically pivot into the non-shielding position,with the hinges thereafter holding the heat shield 40 in suchnon-shielding position against the force of gravity. Where suchspring-loaded hinges are utilized, it may be preferred that the hingesprovide a controlled, slow movement of the heat shield 40 to thenon-shielding position.

[0021] In connection with either embodiment, the number, size and forceor torque rating of the hinges may be selected according to that neededfor the size and weight of the heat shield 40 being used. In theillustrated embodiment the hinges 60 each include one hinge plateconnected to the front panel 14 and another hinge plate connected to theheat shield 40, but it is recognized that other configurations arepossible. For example, two spaced apart hinges could be used to connectthe heat shield to the side panels 18 and 20 of the hood structure,where the hinges each include a single hinge plate connected to the heatshield and a pivot pin or bracket connected to a respective one of theside panels 18 and 20. In any embodiment in which the pivot axis of theheat shield is located proximate to the lower end of the front panel,the heat shield shall be considered pivotally connected to such lowerend of the front panel, regardless of whether the hinge or hingesdirectly contact the front panel.

[0022] Although the invention has been described and illustrated indetail it is to be clearly understood that the same is intended by wayof illustration and example only and is not intended to be taken by wayof limitation. One alternative to the use of the supporting hingesdescribed above would be the use of ordinary, free-pivoting hinges incombination with one or more pressurized piston supports such as thoseused in connection with automobile hoods and tailgates. It is recognizedthat numerous other variations exist, including both narrowing andbroadening variations of the appended claims.

What is claimed is:
 1. A broiler exhaust unit, comprising: a hoodstructure including a front panel, a real panel and first and secondside panels, the hood structure including an open bottom for positioningover a broiler; a heat shield pivotally connected to a lower end of thefront panel for movement between a shielding position toward the openbottom and a non-shielding position away from the open bottom, whereinat least one friction hinge pivotally connects the heat shield to thehood structure; when the heat shield is in the non-shielding position orany one of a plurality of positions between the non-shielding positionand the shielding position, the at least one friction hinge providessupport for the heat shield sufficient to prevent gravity from causingthe heat shield to pivot out of such positions.
 2. The broiler exhaustunit of claim 1 wherein the heat shield includes a plurality of slotstherein, each slot including an associated deflector.
 3. The broilerexhaust unit of claim 1 wherein the at least one friction hinge isconfigured to prevent gravity from causing the heat shield to pivot outof any one of a continuous range of positions between the non-shieldingposition and the shielding position.
 4. The broiler exhaust unit ofclaim 3 wherein the at least one friction hinge comprises a constanttorque hinge.
 5. The broiler exhaust unit of claim 1 wherein the atleast one friction hinge comprises a detent hinge.
 6. The broilerexhaust unit of claim 1 wherein the at least one friction hinge alsoprevents gravity from causing the heat shield to pivot out of theshielding position.
 7. The broiler exhaust unit of claim 6 furthercomprising a movable latching mechanism for preventing movement of theheat shield out of the shielding position even when an external forceapplied to the heat shield would be sufficient to overcome a holdingforce of the at least one friction hinge.
 8. The broiler exhaust unit ofclaim 1 wherein an internal portion of the hood includes at least onegrease extraction baffle.
 9. The broiler exhaust unit of claim 1 whereinthe first and second side panels extend downward beyond the lower end ofthe front panel and when the heat shield is in the shielding position itlies adjacent lower portions of the first and second side panels. 10.The broiler exhaust unit of claim 1 wherein the at least one frictionhinge comprises a plurality of spaced apart friction hinges.
 11. Abroiler exhaust unit, comprising: a hood structure including an airintake for positioning over a broiler and at least one grease extractionbaffle therein; a heat shield pivotally connected to a portion of thehood structure for movement between a shielding position toward the airintake and a non-shielding position away from the air intake, wherein atleast one supporting hinge pivotally connects the heat shield to theportion of the hood structure; when the heat shield is in thenon-shielding position the at least one supporting hinge providessupport for the heat shield sufficient to prevent gravity from causingthe heat shield to pivot out of the non-shielding position.
 12. Thebroiler exhaust unit of claim 11 wherein the at least one supportinghinge comprises one or more constant torque hinges that further providesupport for the heat shield sufficient to prevent gravity from causingthe heat shield to pivot out of any one of a continuous range ofpositions between the non-shielding position and the shielding position.13. The broiler exhaust unit of claim 11 wherein the at least onesupporting hinge comprises one or more detent hinges that furtherprovide support for the heat shield sufficient to prevent gravity fromthe causing the heat shield to pivot out of any one of a plurality ofpositions between the non-shielding position and the shielding position.14. The broiler exhaust unit of claim 11 wherein the at least onesupporting hinge comprises one or more spring-loaded hinges that biasthe heat shield into the non-shielding position.
 15. The broiler exhaustunit of claim 14 further comprising a releasable latch mechanism thatautomatically latches when the heat shield is moved to the shieldingposition, when the latch mechanism is latched it prevents the heatshield from moving out of the shielding position, when the latchmechanism is released the heat shield automatically moves to thenon-shielding position.
 16. A cooking system comprising: a broilerpositioned beneath the broiler exhaust unit of claim 11, and at leastone blower for drawing air into the air intake of the hood structure.17. The cooking system of claim 16 wherein the broiler is a mobile unit,when the heat shield is in the shielding position it blocks the broilerfrom moving away from the hood structure, when the heat shield is in thenon-shielding position it no longer blocks the broiler.
 18. A kitchenexhaust unit for use in connection with a cooking appliance such as abroiler, the unit comprising: a hood structure including an air intakefor positioning over a cooking appliance; at least one grease extractionbaffle within an interior of the hood structure; a heat shield pivotallyconnected to a lower part of the hood structure for movement between ashielding position toward the air intake and a non-shielding positionaway from the air intake, wherein at least one supporting hingepivotally connects the heat shield to the lower part, and the at leastone supporting hinge provides support for the heat shield sufficient toprevent gravity from causing the heat shield to pivot out of thenon-shielding position.
 19. The kitchen exhaust unit of claim 18 whereinthe at least one supporting hinge comprises one or more constant torquehinges that further provide support for the heat shield sufficient toprevent gravity from causing the heat shield to pivot out of any one ofa continuous range of positions between the non-shielding position andthe shielding position.
 20. The kitchen exhaust unit of claim 18 whereinthe at least one supporting hinge comprises one or more detent hingesthat further provide support for the heat shield sufficient to preventgravity from the causing the heat shield to pivot out of any one of aplurality of positions between the non-shielding position and theshielding position.
 21. The kitchen exhaust unit of claim 18 wherein theat least one supporting hinge comprises one or more spring-loaded hingesthat bias the heat shield into the non-shielding position.
 22. Thekitchen exhaust unit of claim 21 further comprising a releasable latchmechanism that automatically latches when the heat shield is moved tothe shielding position, when the latch mechanism is latched it preventsthe heat shield from moving out of the shielding position, when thelatch mechanism is released the heat shield automatically moves to thenon-shielding position.